The ratio of the number of red stickers to blue stickers is 4 : 1.
After Adam buys another 40 red stickers and 90 blue stickers,
the ratio becomes of the number of red stickers to blue stickers is 3 : 2.
How many stickers does Adam have now?
|
Make p the same (1) x 2 = (3) |
(1) Red |
(2) Blue |
Make p the same (2) x 3 = (4) |
Before |
8 u |
4 u |
1 u |
3 u |
Change |
+ 80 |
+ 40 |
+ 90 |
+ 270 |
After |
8 u + 80 |
4 u + 40 |
1 u + 90 |
3 u + 270 |
Comparing the red stickers and the blue stickers in the end |
6 p |
3 p |
2 p |
6 p |
4 u + 40 = 3 p --- (1)
1 u + 90 = 2 p --- (2)
Make p the same by using the LCM of 2 and 3.
LCM of 2 and 3 is 6.
(1)
x 2 8 u + 80 = 6 p --- (3)
(2)
x 3 3 u + 270 = 6 p --- (4)
(3) = (4)
8 u + 80 = 3 u + 270
8 u - 3 u = 270 - 80
5 u = 190
1 u = 190 ÷ 5 = 38
Number of stickers that Adam has now
= 4 u + 40 + 1 u + 90
= 4 u + 1 u + 40 + 90
= 5 u + 130
= 5 x 38 + 130
= 190 + 130
= 320
Answer(s): 320